Filippo Bonchi Antonio Brogi Sara Corfini Fabio Gadducci Compositional Specification of Web Services Via Behavioural Equivalence of Nets: A Case Study. 52-71 2008 Petri Nets http://dx.doi.org/10.1007/978-3-540-68746-7_8 conf/apn/2008 db/conf/apn/pn2008.html#BonchiBCG08